Some common home energy-efficiency problems and tips for how to fix them:
Many air leaks and drafts are easy to find because they are easy to feel — like those around windows and doors. But holes hidden in attics, basements, and crawlspaces are usually bigger problems. Sealing these leaks with caulk, spray foam, or weather stripping can have a huge impact on your comfort and utility bills.
Do you have enough insulation in your attic? One quick way to determine if you need more is to look across the span of your attic. If your insulation is just level with or below your floor joists (i.e., you can easily see your joists), you should add more. If you cannot see any of the floor joists because the insulation is well above them, you probably have enough and adding more may not be cost-effective.
Insulation levels are defined by R-Values. The R-Value is a measure of insulation’s ability to resist (the R in R-Value) heat flow. The higher the R-Value, the more the insulation resists the flow of heat and the better the thermal performance of the insulation. The recommended level for most attics is R-38 or about 10 to 14 inches, depending on insulation type.
The US Department of Energy provides a map of recommended R-Values for various region of the United States along with a handy chart showing how much insulation different parts of your home should have.